Catalyst carrier



Patented May 30, 1944 FFICE H CATALYST CARRIER Johann Adam Bertsch',deceased, late of St. Louis, Mo., by Manufacturers Bank a Trust Companyof St. Louis, executor, St. Louis, Mo.

' No Drawing. Continuation of application serial- No. 318,627, February12, 1940. This application July 29, 1942, Serial No. 452,684

6 Claims.

This invention relates to carriers or supports for catalytic materials,and it has special application to carriers which are suitable for use incatalytic vapor phase chemical reactions.

In the development ofcatalytic processes, considerable attention hasbeen given to the finding of suitable carriers on whichto support theparticular catalyst to be used. As-a result, many materials have beensuggested for use as carriers. Among these materials may be mentionedpumice, clay, asbestor, sand, Alundum, glass wool, kieselguhr, nickel,iron, etc.

Notwithstanding the numerous materials which have been suggested, thereis still need for a suitable carrier. The requirements for carriers areso stringent that it is understandable that such is the case. To mentiona few of these requirements it may be stated that a carrier should beinert under the conditions of th reaction; it should besufilcientlystrong so as to withstand physical stresses; it should notbe affected injuriously during use for a reasonable period; it shouldnot deleteriously affect the production of the desired products; itshould lend itself to the facile charging of and removal from catalyticconverters; etc. It is noted also that the art quite generally holdsthat a suitable carrier should be a. good conductor of heat and that itshould have a rough surface.

This invention has for an object the provision of a novel catalystcarrier which possesses a combe used, are thereby unevenly distributedin the various tubes. flow is also caused by the disintegration duringuse of the fibers of glass wool and asbestos. As is well known,non-uniform resistance to the passage of gases is highly undesirable.Other disadvantages of asbestos and glass wool include the 'pooradhesion of many catalysts thereto, brittleness of glass wool and thelow tensile strength of asbestos. These factors have the effect ofrendering operations dimcult; of reducing reaction rates, of causinglosses in catalytic material; and they are otherwise undesirable. I

It is also known that organic fibrous materials have been suggested ascarriers for use in certain catalytic processes. The disadvantage ofsuch carriers, for example, cotton, hemp, flax, and the like, is thatthey do not withstand the temperatures under which various reactions areconducted. Consequently, the carriers disintegrate and the catalyticmaterials collect at the bottom of the catalyst chamber, conditionswhich are veryv 4 undesirable.

bination of desirable properties not possessed by placed in position ina .catalytic chamber and removed therefrom when desired.

Other objects of the invention will be apparent to thoseskilled in theart from a reading of the following description.

It has now been found that, a carrier which fulfills the foregoing aswell as other objects can be made from flexible glass or quartz fibersin spun, twisted or braided form, for example, in the form of string,cord, rope and the like. This finding is quite unexpected because quartzand glass, as is well known, are rather poor heat conductors and thefibers thereof are smooth. These characteristics would have indicatedthe unsuitability of glass and quartz fibers for use as catalystcarriers.

It is known that glass wool and asbestos have been suggested ascarriers. However, these materials are not suitable in many reactions,for example, the vaporphase oxidation of toluene to benzaldehyde. It isdifficult to fill the tubes of a tubular catalyst reaction vessel evenlywitli these materials without the occurrence of varying degrees ofpacking in the various tubes. The reacting gases, as well as other gaseswhich may The carriers of this invention are characterized in that theyare flexible, fibrous, relatively strong, substantiallytemperature-resistant and inert inorganic materials. The individualfibers have a diameter of the order of 0.001 inch or less, for example0.0003 inch. The physicaljorm of the carriers contemplated by thisinvention is one exemplified by the popular meaning attributed to thewords string, "cord or rope. That is to say, the carriers of thisinvention are quasi-cylindrical or flat in shapeand have a length todiameter or width ratio which is very high. The actual diameter or widthmay vary 1 over rather wide limits, but it is advantageous to usecarriers having a diameter or width ofbetween 2 to 5 millimeters, forexample 2 millimeters. The carriers, coated with cataiyticallyactivematerial, may be attached to suitable sup-.

ports and suspended in parallel or substantially parallel alignment- Itwill be understood that the diameter or width of the carrier, the numberof contact masses per catalyst chamber, and the distance between contactmasses may be varied to fit the requirements or conditions of theparticular reaction. It will be further understood that cloth, gauze andbag forms of glass or quartz are not included within the scope of thisinvention. Glass products coming within this invention are soldcommercially under the name Fiberglas. 1 I

The catalyst to be used may be applied to the carrier in a simplemanner. -'I'lie-catalyti cally.- active material may be applied to thesurface of the carrier by rubbing it' on in the form of a sludge, or byspraying it, or by other methods known to the art. Promoters, such asalkali hydroxides, may be used in connection with the catalyst. Ifdesired, the carrier may be subject- Non-uniform resistance to gas,

applied. i a

The contact mass, comprising the carrier and catalytically-activematerial, may then be treated inknown manner according to the particularcomposition of the catalyst in order to fix it on the carrier in desiredchemical as well as physical form. I

The thickness of the catalyst coating applied to the carrier may also bevaried to suit the individual case. A feature of this invention is thatvery thin coatings are feasible with the hereindisclosed carriers. Theinvention is not to be restricted, however, to any special percentage ofcatalyst coated on the carrier. Moreover, it will be apparent that it isphysically impossible to prevent some catalyst from going below thesurface of thecarrier when the catalyst is applied to the carrier. Theword "deposited in the claimsis to be construed in relation to theforegoing. I

The contact masses prepared according to this invention possessproperties which render them eminently suitable for use in catalyticreactions.

tained. This may be compared with the very difierent situation applyingto carriers in granular form, for example, pellets. whose use renderstroduced until a blue color developed. After diluting the mixture toabout 300 parts of water, 80 parts of 28% strength ammonia solution wereadded. A dark brown paste of tetravalent vanadium' oxide formed. 2 partsof potassium hydroxide were added to the sludge after the latter waswashed with water.

The sludge thus formed was rubbed on to flexible glass cord (Flberglas)of 2 millimeters a part of the catalytic surface ineffective becausesaid part does not come in contact with the-reactants during use.

provision of contact masses comprising the instant carriers andoxidation catalysts for use in connection with various vapor phasecatalytic processes, the invention is not to be limited thereby but isto be construed as broadly as permissible in view of the prior artlimited solely by the appended claims.

This is effectively continuation application 0 of Serial Number 318,627,filed February 12, 1940.

What is claimed as new is:

1. The contact mass comprising a cord-type I carrier selected from thegroup consisting of Another advantage of the herein-disclosed contactmasses is that they render it easyto charge and discharge catalyticchambers or converters. On the other hand, where a granulated .contactmass is used. great care must be exercised in filling converters inorder to insure a uniform .distribution of reactants, which uniformityis extremely desirable in vapor phase catalytic reactions. Wool-likesupports are even harder to apply in such a way as to secure uniformity.The removal .from the converter; of the contact masses herein-disclosedis also a simple operation, as all one has to do is to pull the mass instring, cord, or rope form from the chamber.

The contact masses provided herein lend themselves to use in catalystchambers which may assume any desired position. This is not feasibleriers may be aligned very easily in parallel or' substantially parallelrows in the catalyst chamher, that the desirable objective in vaporphase reactions of obtaining uniform resistance to the passage of gasesis easily attained by the use of said carriers.

' An example illustrating the process of this invention is set forth.All parts are by weight.

A sludge of catalytically-active material was made as follows:

20 parts of pulverized vanadium pentoxide were mixed with 80 parts ofwater and 20 parts of 93% strength sulfuric acid. The contents werebrought to a boil and sulfur dioxide gas was intype carrier,characterized by being flexible,

glass and quartz, characterized bybeing flexible, I

fibrous, relatively strong, relatively temperature resistant and havingan individual fiber diameter of substantially 0.0003 to 0.001 inch, anda catalyst deposited thereon.

2. The contact mass comprising a cord-type carrier selected from thegroup consisting of glass and quartz, characterized by being flexible,fibrous, relatively strong, relatively temperature resistant and havingan individual fiber diameter of substantially 0.0003 to 0.001 inch, andan oxide of vanadium deposited thereon.

3. The contact mass comprising a glass cordtype carrier, characterizedby being flexible, fibrous, relatively strong, relatively temperatureresistant and having an individual fiber diameter of substantially0.0003 to 0.001 inch, and a catalyst deposited thereon.

4. The contact masscomprising a glass cordfibrous, relatively strong,relatively temperature resistant and having an individual fiber diameterof substantially 0.0003 to 0.001 inch, and an oxide of vanadiumdeposited thereon.

5. The contact mass comprising a glass cordtype carrier, characterizedby being flexible, fibrous, relatively strong, relatively temperatureresistant, having an individual fiber diameter of. substantially 0.0003to 0.001 inch and an overall diameter of 2'to 5 millimeters, and acatalyst deposited thereon.

6. The contactmass comprising a glass cordtype carrier, characterized bybeing flexible, fibrous, relatively strong, relatively temperatureresistant, having an individual fiber diameter of substantially 0.0003to 0.001 inch and an'over-all' diameter of 2 to 5 millimeters, and anoxide of vanadium deposited thereon.

MANUFACTURERS BANK 8: TRUST COMPANY OF ST. LOUIS.

Exemztorof the Estate 0! Johann Adam Bertsch,

Deceased,

By HUGH B. ROSE, Trust Oflicer.

CERTIFICATE or CQRRECTION. Patent n sa esm- A 1 M y 5 9 i.

JOHANN ADAM BER'ISCH, DECEASED, by MANUFACTURERS BANK & TRUST COMPANY orST. LOUIS.

EXECUTOR.

It is hereby certified that the ebove numbered patent was erroneouslyissued'to "MANUFACTURERS BANK 8c TRUST COMPANY OF ST. LOUIS. as executorof JOHANN ADAM BERTSCH, deceased whereas said patent should have beenissued to --BURTON T. BUSH, INC. of Delawanna, New Jersey, a corporationof New Jersey", as assignee of the entire interest therein; and that thesaid Letters Patent should be read with this correction therein that theseine may conform to the record of the case in the Patent Office.

Signedv and sealed this 22nd day of August, A. D. 1911.11,.

Leslie Frazer (Seal) Acting Commissioner of Patents.

